Sandal insert



FIG. 1 is a side elevational view showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a perspective view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a front elevational view thereof; and.

FIG. 6 is a plan view thereof.

The ornamental design for a sandal insert, as shown and described.